The Syrian Observatory for Human Rights said Syrian government warplanes dropped barrel bombs on rebel-held areas of Hama province on Tuesday, a day after the United States said their use could lead to further U.S. strikes in Syria.

A Syrian military source denied the Observatory report and said the army did not use barrel bombs - drums or cylinders packed with explosives and shrapnel that cause indiscriminate destruction on the ground.

The United States fired cruise missiles at a Syrian air base last week in response to a poison gas attack on a town in northwestern Syria which Washington says was carried out by government forces. The government denies responsibility.

The Observatory said “a number” of barrel bombs had been dropped on the towns of Taybat al-Imam and Soran north of Hama city in an area where rebel groups spearheaded by jihadist factions launched a major offensive last month.

Observatory director Rami Abdulrahman said the number of barrel bombs dropped by government warplanes was relatively small. U.N. investigators have recorded regular use of such bombs by government forces in Syria.

White House spokesman Sean Spicer on Monday mentioned barrel bombs alongside poison gas as weapons that were causing “babies and children” to suffer. “If you gas a baby, if you put a barrel bomb into innocent people ... you will see a response from this president,” he said.

The Syrian military source said: “We do not use these barrels and they do not exist in the Syrian Arab Army.”

Army operations were continuing across Syria, and “will not stop”, the sources said.

(Chip Somodevilla/Getty Images)

Sean Spicer can’t possibly mean what he just said about Syria. Can he?

White House press secretary Sean Spicer just announced a policy that would mean constant and unending US involvement in Syria’s civil war — if the Trump team is actually serious about it.

During a daily press briefing on Monday, Spicer was asked what Bashar al-Assad’s regime could do to trigger another bombing attack like the one last Thursday. Would it have to be a chemical weapons attack, or would more conventional bombings targeting civilians also trigger US retaliation?

Spicer’s answer was surprising. He said that additional US intervention could be triggered if Assad were to use poison gas on civilians again — or if he were to use a kind of conventional explosive called a barrel bomb (emphasis mine):

Q: Is the red line for this White House chemical warfare? Is conventional warfare enough to get the president to go further than this White House is going?

SPICER: I think the president has been very clear that there are a number of lines that were crossed last week. He’s not going to sit down — you saw this with the last administration, they drew these red lines, and then the red lines were run over. ... The answer is that if you gas a baby, if you put a barrel bomb into innocent people, I think you will see a response from this president. That is unacceptable.Barrel bombs are containers filled with explosives and sometimes metal, dropped from helicopters, often on civilian areas. Assad’s air force uses them extremely frequently — his forces dropped 13,000 of them in 2016 alone, according to the Syrian Network for Human Rights. That’s roughly 36 barrel bombs a day.

By comparison, the chemical weapons attack last week was the first use of banned nerve agents by the Syrian government since 2013. Given the rarity of such attacks, threatening US retaliation for each one makes a certain kind of sense — especially if your goal is only to send a signal that chemical weapons use is unacceptable without getting more deeply involved in the civil war.

But if Trump’s new policy is that the US will bomb Assad every time there’s a barrel bomb attack that kills civilians, as Spicer plainly suggested, then the US will be bombing Assad every day. America will be engaged in a full-scale war against Assad, whether the Trump people call it that or not.

This policy seems so at odds with everything else the administration is saying — all officials, including Spicer, have suggested the US doesn’t intend to topple Assad by force — that it’s hard to believe Spicer meant what he said. Yet he repeated the line later in the briefing, saying that barrel bombs could trigger “further action” from the United States.

The simplest explanation is that Spicer just doesn’t know what a barrel bomb is. That he assumes it’s some kind of chemical weapon, or somehow more evil than any other kind of bomb Assad regularly uses on civilians. If that’s true, then Spicer’s screw-up has put Trump in a deeply awkward place. His own press secretary just declared barrel bomb use a “red line” — yet Assad is almost certain to use barrel bombs against civilians in the next 24 hours.

Either the Trump administration has to publicly repudiate Spicer’s comments, humiliating their press secretary and further undercutting his ability to speak for the president (which is his entire job). Or they ignore it, and leave the kinds of actions by Assad that will trigger US intervention radically unclear.

Syria crisis: Barrel bombs dropped by government, activists say

One day after White House Press Secretary Sean Spicer warned that the use of barrel bombs in Syria would provoke an additional U.S. response, opposition activists say the regime of President Bashar al-Assad is, in fact, dropping the deadly weapons.

Syrian helicopter gunships deployed as many as eight barrels loaded with explosives over the city of Daraa after rebel fighters stormed the government-held area, according to the Britain-based Syrian Observatory for Human Rights. The military dropped additional barrel bombs over rebel-held areas in Hama province farther north, the activists said.

The extent of the damage and destruction was unclear.

Spicer said Monday at the White House that President Trump stood ready to take more action in Syria if necessary, days after the Pentagon reported it launched nearly 60 Tomahawk missiles on a government-controlled base. "If you gas a baby, if you put a barrel bomb in to innocent people, I think you will see a response from this president," Spicer said.

The Trump administration quickly moved to clarify that Spicer was not effectively drawing any new "red lines." A White House statement read, "Nothing has changed in our posture."

By Tuesday, the fighting on the ground in Daraa had killed as many as 16 pro-government troops including an army colonel, the Observatory said. Activists added that Syrian warplanes were conducting raids on Daraa as well.

Secretary of State Rex Tillerson on Tuesday made the Trump administration's position clear: Time has run out for the Assad regime. "It is our policy for a unified Syria that is governed by the people of Syria. I think it is – it’s clear to all of us that the reign of the Assad family is coming to an end," Tillerson said on the sidelines of the Group of Seven (G-7) meeting in Italy.

Damascus again denied using some of the most powerful weapons seen in the six-year civil war. "We do not use these barrels and they do not exist in the Syrian Arab Army," a Syrian military source told Reuters.